Measuring Images
Mira provides many tools for measuring and quantifying images, including distance and angle, statistics, photometry, shape measurements, and others.
Measurement procedures are operated through buttons, menu commands, and command toolbars. Measurements share a common user interface in terms of how the target object is marked and how the results are displayed in a Grid Control. You can also create a scatter plot, including error bars, from two columns in a table of measurements. Other types of plots and point samples are also useful for quantifying images.
Measurements are divided into classes according to whether they use the Image Cursor or the Mouse Pointer to mark locations. All measurements that use a toolbar use the mouse pointer. Conversely, all measurements that use the image cursor operate from a button (or a duplicate entry in a menu). All Command Toolbars all have a similar interface
Thesecommands list their results in a Report Window or a Measurement Pane (the default for a new Mira installation). They also have menu commands in case the button is not accessible..
Centroid: Reports a high precision position for a peak or trough.
Statistics: Reports statistics inside a rectangular region.
To change the destination of the measurement, choose the destination using the drop-menu next to the command icon in the Cursor Tools Toolbar.
Edit Pixel Values: Displays the values of pixels inside the image cursor as a 2-dimensional grid. Simple pixel value editing can be done from the grid.
These commands list their results in a Measurement Pane:
Distance & Angle: Measures the distance and angle between two points.
Aperture Photometry: Makes photometric measurements of stars and other objects.
Image Coordinate Readout: The "live" cursor in the image window measures image coordinates and values.
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Tip |
The difference between measurements made by the mouse pointer and image cursor is generally as follows: Measurements that use a window toolbar use the mouse pointer to mark or drag markers on the image. Measurements that use menu commands and buttons on the Image window or main toolbar use the Image Cursor as a position reference. |
Contents, Grid Controls, Measurement Panes, Report Windows, Command Toolbars, Image Windows, RGB Image Commands, Scatter Plot